165787 has 4 divisors (see below), whose sum is σ = 166840. Its totient is φ = 164736.

The previous prime is 165779. The next prime is 165799. The reversal of 165787 is 787561.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 787561 = 89 ⋅8849.

It is a cyclic number.

It is not a de Polignac number, because 165787 - 2³ = 165779 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (165707) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 237 + ... + 622.

It is an arithmetic number, because the mean of its divisors is an integer number (41710).

2¹⁶⁵⁷⁸⁷ is an apocalyptic number.

165787 is a deficient number, since it is larger than the sum of its proper divisors (1053).

165787 is an equidigital number, since it uses as much as digits as its factorization.

165787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1052.

The product of its digits is 11760, while the sum is 34.

The square root of 165787 is about 407.1694978753. The cubic root of 165787 is about 54.9351301307.

The spelling of 165787 in words is "one hundred sixty-five thousand, seven hundred eighty-seven".